Door lock with safety device



Nov. 14, 1967 F. D. CROSSWELL ET AL ,5

DOOR LOCK WITH SAFETY DEVICE Filed Aug. 2, 1965 2 Sheets-Sheet 1 F75.j, F/E.2.-

Nov. 14, 1967 F. D. CROSSWELL ET AL 3 5 DOOR LOCK WITH SAFETY DEVICE 2 Sheets-Sheet 2 Filed Aug. 2, 1965 Fla W F M United States Patent C) 3,352,585 DOOR LOCK WITH SAFETY DEVICE Flay D. Crosswell and John W. Binns, Marion, hio, as-

signors to Overhead Door Corporation, Hartford City, Ind., a corporation of Indiana Filed Aug. 2, 1965, Ser. No. 476,586 7 Claims. (Cl. 292-92) ABSTRACT OF THE DISCLOSURE A safety lock device for overhead truck-trailer doors comprising a conventional locking mechanism on the outside of the door integrated with a safety lock which is accessible only from the inside of the door.

The conventional outer locking mechanism is attached to a metal plate. The plate is in turn fastened to the overhead truck door by the inside safety lock. The inside safety lock comprises a handle, accessible only from the inside of the truck door, which when turned causes a locking pin in the truck door to engage or disengage the metal plate holding the outer locking mechanism.

This invention relates to an improved locking device particularly for use with doors used for trucks and the like wherein a safety or life-saving feature is provided so that the lock may be rapidly unlocked from within the truck.

US. Patent No. 3,108,833 describes a highly acceptable lock for truck doors, particularly for upwardly acting sectional doors. Although this lock is highly satisfactory, the lock has one significant disadvantage since there is no way for anyone trapped within the truck to open the door from the inside. Although being trapped within a truck is usually only an inconvenience and would not ordinarily present any threat to the life of a person trapped within the truck, the situation is radically different in the case, for example, of refrigerator trucks using expandable gas, as nitrogen systems, now in common use. Thus, if a person is trapped behind a locked or latched door, when the gas system is operating, the trapped person would rapidly suffocate or freeze to death if there was no way of opening the truck door from the inside.

It is therefore an important object of this invention to provide a unique lock assembly for doors wherein a door may be rapidly opened from within the enclosed space so that a person may get out of the truck rapidly.

It is also an object of this invention to provide a unique door look assembly particularly for trucks and trailers wherein the lock assembly includes a unique mechanism which enables a person to rapidly open the truck door from the inside although the look itself remains in a normally latched or locked condition.

It is another object of this invention to provide an improved truck door lock assembly wherein the door may be rapidly and completely disengaged from the locking portion of the assembly so as to permit a latched or locked door to be opened from inside the truck.

It is still another object of this invention to provide a life saving door lock device which is normally latched and locked only from the outside of the door, but which includes a unique mechanism on the inner sunface of the door to permit the truck door to be raised from the inside.

It is a further object of this invention to provide an improved life saving truck door device which is characterized by its simplicity and economy of construction, -manufacture, and use.

Further purposes and objects of this invention will appear as the specification proceeds.

"ice

A particular embodiment of the present invention is illustrated in the accompanying drawing wherein:

FIGURE 1 is a front elevational view of our improved life saving door lock assembly, as viewed from the exterior, while in the locked position;

FIGURE 2 is a sectional view taken along the line 2-2 of FIGURE 1;

FIGURE 3 is a view similar to FIGURE 1 except that the door is shown in the raised position after operation of the life saving mechanism of our lock assembly;

FIGURE 4 is a sectional view taken along the line 44 of FIGURE 3;

FIGURE 5 is a view of the embodiment of FIGURES l and 2 as viewed from the interior;

FIGURE 6 is a view of the embodiment of FIGURES 3 and 4 as viewed from the interior; and

FIGURE 7 is a front elevational view of our locking device in the unlatched position to permit the door to be opening in the conventional manner.

Referring to the drawings and particularly to FIGURE 7, our locking device, generally 10, is fixedly connected to the lower and outer central portion of an upwardly acting sectional door D and is shown in the conventional unlatched and unlocked position.

The locking device 10 includes a handle 12 which is integral with a central housing portion 14. As seen in FIGURE 7, the housing 14 is pivotally carried by a pin 16. A normally downwardly extending locking arm 18 is pivotally carried by a pin 20 which is secured within 30 the housing 14, the pin 20 being substantially parallel to and spaced from the housing pivot pin 16 so that the locking arm 18 is eccentrically pivoted within the housing. A tension spring 22 within the housing 14 is connected 'to the arm near its pivot so as to normally bias the locking arm 18 toward the handle portion 12 to provide positive force for the maintenance thereof in the latched or unlatched position, as desired. The locking arm 18 includes an offset or arcuate portion 24 which, when the locking arm 18 is down in the locked position shown in FIGURE 7, enables the arm 18 to circumvent the pivot pin 16. In order to engage the hooked end of the locking arm within the fixed locking pin 26 in the floor of a truck or the like, the operator rotates the handle 12 in a clockwise direction as seen in FIGURE 7, to the dotted line position shown therein. During this motion, the hooked end 27 of the arm swings below the pin 26 and moves up into engagement therewith, due to 'the eccentric location of the pin 20, as the handle 12 is moved to the locked position shown in FIGURES 1 and 2. In the fully locked position, the handle portion 12 is in a substantially horizontal position, and desirably a latching mechanism 28 is provided to maintain the device 10 in the locked position.

Referring more particularly to FIGURES 2 and 3 the operating handle 12 is provided with a downwardly extending portion or integral plate 30 which includes an aperture through which the loop of a padlock 32 may be passed. The loop of the padlock also passes through an aperture in an outwardly extending plate portion 34 of a locking plate 36 so as to maintain the plate portion 34 and the downwardly extending portion 30 in simultaneous locking engagement with the padlock 32.

What has been generally described heretofore is what is generally shown in the aforesaid Patent No. 3,108,833.

Our invention, however, includes further structure which enables the truck door D to be opened from the inside even though the handle 12 and arm 18 are in the fully locked or latched position such as shown in FIGURESl and 3. Since an individual, as a person loading or unloading the truck, may inadvertently become locked within the truck, it is imperative in certain instances that the trapped individual be able to free himself from within the truck rapidly. Thus, it is important in our invention that detachable engagement be provided between the lock 10 and the door D.

In order to provide for this detachable engagement, a retainer ,plate, generally 38, is fixed, for example, to the outer and lower portion of an upwardly acting sectional door D. The retainer plate 38 includes a downwardly extending upper flange 46 and inwardly extending lateral flanges 42. The locking plate 36 to which the housing 14 is pivoted at 16, to which the latching mechanism 28 is affixed, and of which the plate portion 44 is apart, is slidably received and engaged by the fianges'40 and 42 so thatthe locking plate 36 and retainer plate 38 are normally maintained adjacent each other. The lateral edges 44 of the locking plate 36 are converged inwardly and upwardly so that the locking plate readily moves into sliding engagement with the retainer plate 38 through the unflanged lower end of the retainer plate.

As seen in FIGURE 1, when the retainer plate 38 and the locking plate 36 are adjacenteach other and in the locked position, the locking plate 36 isprevented from forward movement by the flanges 40 and 42, from upward movement relative to-the door by the upper flange *40, and from lateral movement by the flanges 42. Thus,

the only possible movement for the locking plate 36,

when adjacent the retainer plate 38 is movement through the unflanged lower end of the retainer plate 38. Therefore, in order to normally prevent all relative movement between the locking plate and the retainer plate and thereby the door, it is important that a plate engaging device 46 be mounted within the door D for simultaneously and detachably engaging the plates 40 and 42.

The engagement device 46 includes a horizontally slidable pin member 48 which is reciprocally mounted within an aperture 50 in the door D. The reciprocating pin 48 passes through the normally aligned apertures 52 and 54 in the retainer plate 38 and locking plate 36, respectively. Thus, as seen in FIGURE 2, in the normal engaged position, the pin 48 simultaneously extends through the aligned plate apertures 52 and 54 so as to'prevent all relative movement between the retainer'and locking plates 38 and 36, since it normally prevents the only possible relative movement betweenthe plates 36 and 38 when they are adjacent each other.

In order to maintain the .pin in normal engagement with the apertures 52 and 54, a compression spring 56,

located within the aperture 50, is positioned around the pin 48, and acts against an'annular shoulder 58, provided intermediate the outer ends of the pin'48. The-inner end of thecompression pin 56 *bearsagainst theinner surface of a cam support plate 60 which is in a rectangular depression 65 and-is secured by any suitable means to the inner depressed surface of the door'D. Inthis man- -ner,'the spring normally biases the pin 48 into locking engagement with the lock plate 36.

Referring particularly to FIGURES 2, 4, -and'6, the

inner surface of the upwardly acting sectional door D includes a depression'62 having an "arcuate portion 63 and a rectangular portion'65 for-receiving the actuating mechanism'64 for moving the pin 48 out of its-normal engagement with the lock plate aperture 54. Specifically a retractable elongated handle or-arm 66-is fixedly secured to the'inner endof the pin 48-'as is a camfollower means 68. This cam followercooperates with'and rides upon camming surfaces 70 on the outer surface of the support plate '60. The camming surfaces 70, as seen in'FIGURE 4, are each tapered outwardly so that, as the-handle-66'is rotated, thefollower 68 and pin 48 are simultaneously rotatedrDuring this rotation, each of the cam followers 68 rides outwardly on the respective icooperating camming surfaces-70and thereby move the pin- 48 outwardly from engagement with the locking plate aperture, '54. At the outer or raised'end of .the camming surfaces 70, shallow depressions -72'are provided soas .tomaintain the handle 66-and pin 48 inthe. disengaged position by preventing reverse movement of the cam followers 68 back down the cam surfaces 70.

In the use of the aforedescribed device 10, in the event a person becomes inadvertently locked within the confines of a truck and the door D is latched and/or locked, the person within the truck may quite rapidly open the door from within. Referring particularly to FIGURE 15, the handle 66 for accomplishing disengagement between the locking plate 36 and the door D is shown in the normally locked position. A bracket 74 is affixed within the arcuate depression 63 on the inner surface of the door D and a wire type seal 76 is passed through suitable apertures provided in both the bracket 74 and the handle 66. The seal 76 prevents the pin member 48 from being disengaged from the lock plate 36 from outside of the truck since of the pin 48 is prevented.

The person within the truck maybreak the seal 76 merely by rotating or forcing the handle 66 in a downward direction, or, as viewed in FIGURE 5, in a counterclockwise direction. This rotation causes the cam followers 68 to be raised or moved inwardly as they ride on the cam surfaces 70. Since the pin is affixed-to the follower member 68, the pin '48 also moves inwardly and out of engagement with the aperture 54 in the lock plate 36. When the handle 66 has been rotated to the fully open position, the cam followers-6'8 dropinto the depressions 72 of the camming surfaces 70. At this time, the lock plate and locking device 10 are disengaged from the door D and the trapped person may grasp the handle 78 provided on the inner surface of the door and lift the door upwardly. It is thus seen in FIGURES 4'and 6'that the door D is open, although the locking plate 36 and padlock 32 are still in the locked position.

In order to place'the locking device 10 and lock plate 36 back into engagement with the door D, the padlock 32 'is'unlocked, and the handle 12 is rotated to the normal open position as shown in FIGURE 7. The locking plate 36 is then separated from engagement with the locking device 10. The plate is then slid into normal engagement with the retainer plate 38 and with the flanges 40 and 42 so that the apertures '52 and 54 are aligned. The handle 66 is rotated from the position of FIGURE 6 to the position of FIGURE 5. A seal is again installed in the apertures provided in the bracket 74 and handle66. During the reverse movement of the handle 66, the camfollowers 68 move downwardly or outwardlyion the cam surfaces and the spring 56 forces the pin 48back into engagement with the aligned apertures 52 and 54-so that the door is again in engagement with the lock plate 36 and the lock 10 is ready-for normal use.

While in the foregoing there has been provided a detailed description of -a particular embodiment of the present invention, it is to be understood that all equivalents obvious to those having skill in the art are to be included within the scope of the invention as claimed.

'What we claim and desire to secure by Letters Patent is:

1. A life saving door locking device which enables an individual to rapidly open a door from the side opposite to its locked side, said device comprising a retainer plate fixedly mounted on the locked side of said door, a lock plate normally partially engaged by said retainer plate, a locking means mounted on said lock plate for locking said door in a closed position, means movably carried by said door for normally-engaging said lock plate and means accessible only from said opposite side for disengaging said-engaging-means from said lock plate whereby said door may be moved to the open position from said opposite side without unlocking said locking means.

2. A life saving door lock device which enables a :door to be opened from the inner side while the door remains locked from the outer side, said device comprising a remounted on said lock plate for locking said door in closed position, slidable means mounted within said door for normally connecting said lock plate with said door, and means accessible only from said inner side for disconnecting said slidable means from said lock plate whereby said door may be moved to the open position from the inner side of said door without requiring unlocking said locking means.

3. A life saving door lock device for use with an upwardly acting sectional door having an inner side and an outer side, said device comprising a retainer plate fixed to the outer side of said door, a lock plate normally coextensive and adjacent said retainer plate, said retainer plate maintaining said lock plate in partial engagement therewith, aligned apertures in said lock plate and in said retainer plate, a pin member normally passing through said aligned apertures and being carried by said door for normally maintaining said lock plate in full engagement with said door, handle means accessible on the inner side of said door and being fixed to said pin means, and cam means on the inner side of said door and cooperating with cam follower means on said handle means whereby as said handle means is actuated, said pin moves out of said aligned apertures in response to movement of said cam follower means on said cam means to thereby release said lock plate from engagement with said door whereby said door may be raised without unlocking said locking device.

4. The device of claim 3 wherein said retainer plate includes means for preventing said lock plate from moving both laterally and forwardly, and also from relative vertical movement in one direction.

5. A life saving door locking device for use with an upwardly acting sectional door having an inner side and an outer side, said device comprising a retainer plate fixed to the outer side of said door, upper and lateral retainer flanges on said retainer plate, a lock plate normally coextensive with said retainer plate and in engagement with said flanges, a locking means for locking said door in closed position mounted on the outer side of said door and on said lock plate, aligned apertures in said lock plate and in said retainer plate, biased pin means to normally maintain said lock plate in fixed position relative to said door, said pin means being reciprocally carried by said door, and handle means accessible only from the inner side of said door for moving said pin means out of said aligned apertures whereby said lock plate is movable with respect to said door so that said door with said retainer plate may be lifted upwardly While said lock plate and said locking means remain in the same position at all times.

6. The device of claim 5 wherein cam and cam follower means are provided on the pin means and on the inner side of said door for reciprocally moving said pin means away from engagement with said aligned apertures to effect the desired release of said lock plate from said door.

7. The device of claim 6 wherein a handle is positioned on the inner side of said door to facilitate the raising of said door.

References Cited UNITED STATES PATENTS 901,470 10/1908 Rankins 292-61 2,079,167 5/ 1937 Hafstad 292- 2,250,447 7/1941 Dwyer 292-376 2,340,470 2/ 1944 Haseltine 292-376 2,618,498 11/ 1952 Schlesser 292-376 3,108,833 10/1963 Christensen et al. 7"-113 MARVIN A. CHAMPION, Primary Examiner J. R. MOSES, Assistant Examiner. 

1. A LIFE SAVING DOOR LOCKING DEVICE WHICH ENABLES AN INDIVIDUAL TO RAPIDLY OPEN A DOOR FROM THE SIDE OPPOSITE TO ITS LOCKED SIDE, SAID DEVICE COMPRISING A RETAINER PLATE FIXEDLY MOUNTED ON THE LOCKED SIDE OF SAID DOOR, A LOCK PLATE NORMALLY PARTIALLY ENGAGED BY SAID RETAINER PLATE, A LOCKING MEANS MOUNTED ON SAID LOCK PLATE FOR LOCKING SAID DOOR IN A CLOSED POSITION, MEANS MOVABLY CARRIED BY SAID DOOR FOR NORMALLY ENGAGING SAID LOCK PLATE AND MEANS ACCESSIBLE ONLY FROM SAID OPPOSITE SIDE FOR DISENGAGING SAID ENGAGING MEANS FROM SAID LOCK PLATE WHEREBY SAID DOOR MAY BE MOVED TO THE OPEN POSITION FROM SAID OPPOSITE SIDE WITHOUT UNLOCKING SAID LOCKING MEANS. 